Debt - Schedule of Long Term Debt (Detail) - USD ($) $ in Millions	Sep. 30, 2020	Dec. 31, 2019
Debt Instrument [Line Items]
Finance lease obligations	$ 82.8	$ 71.2
Total long-term debt before discount	2,709.4	2,740.1
Less: unamortized debt issuance costs and discount on debt	(21.4)	(26.3)
Total long-term debt	2,688.0	2,713.8
Less: current maturities	(27.6)	(25.0)
Total long-term debt, excluding current maturities	2,660.4	2,688.8
Term B-3 Loan Due 2024
Debt Instrument [Line Items]
Aggregate principal amount	$ 1,264.1	$ 1,438.0
Variable interest rate	2.40%	4.05%
Term B-5 Loan Due 2026
Debt Instrument [Line Items]
Aggregate principal amount	$ 397.0	$ 400.0
Variable interest rate	2.15%	3.80%
North American ABL Due 2024
Debt Instrument [Line Items]
Aggregate principal amount	$ 337.9	$ 200.0
Variable interest rate	2.00%	5.25%
Canadian ABL Facility Due 2022
Debt Instrument [Line Items]
Aggregate principal amount	$ 127.6	$ 130.9
Variable interest rate	2.73%	4.31%
Unsecured Notes Due 2027
Debt Instrument [Line Items]
Aggregate principal amount	$ 500.0	$ 500.0
Fixed interest rate	5.13%	5.13%

Debt instrument unamortized discount and issuance cost.

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- Definition

Long Term Debt and Finance Lease Liability, Gross

+ References

No definition available.

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- Definition

Long-Term Debt And Finance Lease Obligations

+ References

No definition available.

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- Definition

Amount, before unamortized (discount) premium and debt issuance costs, of long-term debt. Includes, but is not limited to, notes payable, bonds payable, commercial loans, mortgage loans, convertible debt, subordinated debt and other types of debt.

+ References

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- Definition

Line items represent financial concepts included in a table. These concepts are used to disclose reportable information associated with domain members defined in one or many axes to the table.

+ References

No definition available.

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- Definition

Present value of lessee's discounted obligation for lease payments from finance lease.

+ References

Reference 1: http://www.xbrl.org/2003/role/disclosureRef
-Publisher FASB
-Name Accounting Standards Codification
-Topic 842
-SubTopic 20
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- Definition

Amount of long-term debt and lease obligation, classified as current.

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- Definition

Amount of long-term debt and lease obligation, including portion classified as current.

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No definition available.

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- Definition

The interest rate applicable to the portion of the carrying amount of long-term borrowings outstanding as of the balance sheet date, including current maturities, which accrues interest at a set, unchanging rate.

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